Snow plow



Sept. 10, 1968 P IT 3,400,475

SNOW mow Filed May 28, 1965 70 NEUTRAL 7 DOWN u ,-4O 72 I H 2 -':RESERVOIR INVENTOR. JOSEF PElTL BY 7114M a Bad;

ATTORNEYS United States Patent 3,400,475 SNOW PLOW Josef Peitl, Vienna, Austria, assignor to Meyer Products Inc., Cleveland, Ohio, a corporation of Ohio Filed May 28, 1965, Ser. No. 459,568 4 Claims. (CI. 37-42) ABSTRACT OF THE DISCLOSURE A snow plow to be attached to the front end of the sprung part of a propelling vehicle and having an hydraulic raising and lowering mechanism so arranged as to transfer part of the sprung weight of the vehicle to the cutting edge of the snow plow. The cutting edge is formed from a plurality of retractable blades. The mechanism for mounting the blades is so arranged as to tilt the upper edge of the blade forward when the cutting edge is pressed downwardly to take part of the sprung weight of the vehicle so that the supporting slides on the back of the blade will be raised out of contact with the ground.

This invention pertains to the art of snow plows and more particularly to a snow plow mounted on the front end of a motor vehicle.

It has been conventional in the past to mount a snow plow blade on the front end of a motor vehicle so arranged that the blade may be raised into an inoperative position and lowered into contact with the ground by means of hydraulically operated mechanism. Usually the plow blade is provided with skids or wheels located just behind the cutting edge which slide along the ground and determine the clearance between the lowermost portion of the cutting edge and the ground. This clearance may be adjusted from zero to as high as one inch. Normally it will be on the order of one-quarter of an inch.

It has also been known to provide snow plow blades with a cutting edge made up of a plurality of fiat fingers mounted for movement in an upward and backward direction, but spring-biased to the downward and forward position. Each finger when it strikes an obstruction is forced to retract and as it does so, moves upwardly so as to automatically clear the obstruction and when once cleared, to return to its normal advanced position.

One of the problems with snow plows has been to remove hard packed snow or ice, particularly from rough surfaces such as cobblestones or when there are numerous obstructions such as airport runways with their runway marking lights and the like.

The present invention contemplates a snow plow which overcomes all of the above-referred to difiiculties and others andenables hard packed snow and ice to be readily removed from any kind of a road surface.

In accordance with the invention, a snow plow blade is mounted on the front end of a propelling motor vehicle in such a manner that it can be moved vertically upwardly and downwardly relative to the motor vehicle and means are provided for transferring part of the weight of the motor vehicle to the cutting edge of the snow plow blade so that the unit pressure of the edge against the road surface can be increased substantially beyond that of the weight of the plow blade and its supporting mechanism.

Further in accordance with the invention, the mounting mechanism is so arranged that as the weight of the vehicle is transferred to the plow blade edge, the plow blade will tilt forwardly an amount such as to raise the skids 011 the ground and allow the blade edge to contact the ground under substantial pressure.

Further in accordance with the invention, the cutting 3,400,475 Patented Sept. 10, 1968 edge is formed of a plurality of upwardly and rearwardly retractable fingers biased downwardly and forwardly so that as the weight of the vehicle is transferred to the edge, the edge may ride over road surface irregularities.

Further in accordance with the invention, a method of plowing snow with a plow blade having its cutting edge formed of a plurality of fingers which are rearwardly and upwardly retractable, but biased to the forward and downward position comprising moving the blade along the earths surface and transferring part of the weight of the propelling vehicle to the cutting edge so that the fingers are pressed against the earth with a weight greater than that of the plow blade and its supporting structure.

The principal object of the invention is the provision of a new and improved snow plow which can readily and quickly remove hard packed snow and ice from any kind of a surface, whether rough or smooth.

Another object of the invention is the provision of a new and improved snow plow having retractable fingers engaging the earths surface and means for transferring the weight of the propelling vehicle to the plow blade cutting edge.

Another object of the invention is the provision of a new and improved supporting arrangement for a snow plow having the usual skids for controlling the clearance of the cutting edge relative to the earths surface which automatically raises such skids when the weight of a motivating vehicle is transferred to the plow blade.

The invention may take physical form and certain parts and arrangements of parts, a preferred embodiment of which will be described in detail in this specification and illustrated in the accompanying drawings which are a part hereof and wherein:

FIGURE 1 is a side view partly in cross section of the forward end of a motor vehicle having a snow plow mounted on the front end thereof as shown in the normal plowing position; and,

FIGURE 2 is a view similar to FIGURE 1 but showing the blade in a position such that the weight of the vehicle has been transferred to the plow blade.

Referring now to the drawings wherein the showings are for illustrating a preferred embodiment of the invention and not for the purposes of limiting same, FIGURE 1 shows a motor vehicle A having a' snow plow B mounted on the front end thereof for vertical movement relative thereto by means of a hydraulically actuated bracket mechanism C.

The vehicle A forms no part of the present invention and is shown relatively schematically. Such vehicle A includes the usual front rubber-tired wheels 10 mounted so as to be steerable on an axle 11 which in turn supports the chassis 12 through a conventional spring mechanism such as the leaf springs 13. Obviously, the springs can be coil springs, hydraulic springs or the like. The wheels 10 may be power driven as is conventional in large vehicles of this type. The principal thing about the vehicle A is that the frame 12 be spring mounted relative to the wheels 10 such that when an upward force is applied to the frame 12, the frame 12 may move upwardly relative to the earth or road surface 15 on which the wheel 10 rolls, the springs 13 flexing to permit this movement. When the plow is not in engagement with the ground 15, the entire weight of the plow B, its supporting bracket mechanism and the front end of the vehicle is transferred to the wheels and ground through the springs 13.

The plow blade B per se forms no part of the present invention and again it is shown somewhat schematically. The plow consists of the usual curved, forwardly facing, concave mold board 20 reinforced by brackets 21 welded to the back surface thereof, which brackets in turn are welded to a supporting plate 22. The lower or cutting edge of the plow B is, in accordance with the invention, formed from a plurality of fiat fingers which form a forward and downward extension of the lowermost portion 25 of the mold board 20. Each finger 25 is supported in the plow B so as to be retractable in an upward and rearward direction and is biased forwardly and downwardly by means of a helical coil spring or springs 27 bearing at the forward end against the rearward end of the finger 25 and at the rear end against the base of a cylinder welded to one of the reinforcing brackets 21. The specific construction of the mechanism for urging the fingers 25 forwardly forms no part of the present invention. One arrangement for supporting such fingers 25 is shown in my Patent No. 2,962,821, issued Dec. 6, 1960. Another arrangement is shown in US. Patent No. 2,ll6,35l, issued May 3, 1938.

The fingers may have any desired width, but the narrower that such fingers are, the greater sensitivity they will have to obstructions which they encounter and the more readily will they be able to conform to transverse curvatures in the roads surface. A width of seven to ten inches has been found quite adequate in practice.

The leading edge of the fingers 25 will, of course, be angled relative to the fore and aft axis of the vehicle A as is conventional.

Skids 30 are provided for controlling the clearance of the leading edge of the fingers 25 from the road surface 15. These skids 30 may take any desired form including wheels, but in the embodiment shown, comprise shoes having a lower wear surface and an upwardly facing ball socket. A threaded shaft 31 has a mating ball 32 on its lower end and this shaft 31 is threaded into a suitable opening in the supporting plate 22. By rotating the shaft 21, the clearance of the leading edge of the fingers 25 can be readily controlled. A nut 33 on the shaft 31 is tightened when the desired adjustment has been obtained. It is to be noted that, as will appear hereinafter, this adjustment should be made after the plow blade has been installed on the vehicle A. Obviously, any means of adjustably supporting the skids behind the cutting edge of the plow may be employed.

The plow B is mounted on the front end of the vehicle A by means of the bracket mechanism C. Thus, a plate is welded to the front end of the frame 12. The rear plate 41 of the bracket C is mounted on this plate 40 by any suitable means such as the studs 43 welded to the plate 41 and extending through suitable openings in the plate 40. Nuts 44 complete the fastening action. The bracket C also includes a forward plate 45 having a plane spaced forwardly from and generally parallel to the rear plate 41. This plate 45 is mounted for vertical movement relative to the plate 41 by means of a pair of upper toggle members 46 and a pair of lower toggle members 47, which toggle members are pivoted at their forward ends to a rearwardly extending flange 49 integral with the forward plate 45 and at their rearward end to a forwardly extending flange 48 integral with the plate 41. In accordance with the invention, the mounting of the plate 45 relative to the plate 41 is such that when the plate 45 is moved vertically relative to the plate 41, its angle will change relative thereto and in particular so that when the plate 45 moves downwardly relative to the plate 41, its lowermost edge will move in a downwardly and rearwardly extending are. To accomplish this, the upper toggle members 46 are shorter than the lower toggle members 47 and normally extend generally horizontally while the lower toggle members 47 extend generally forwardly and downwardly.

In accordance with the invention, the bracket C includes means for forcefully moving the plow B not only in an upward direction so that the edge of the fingers 25 may be raised above the pavement 15, but more importantly so that the leading edge of the fingers 25 may be pressed downwardly into pressure engagement with the pavement 15 in Such a manner that at least some of the sprung weight of the motor vehicle A may be transferred to the plow B and thus to the pavement 15 through the leading edge of the fingers 25. Such mechanism may take a number of ditferent forms but in the embodiment of the invention shown, is comprised of a cylinder 60 articulately mounted at its upper end relative to the plate 41 by means of a transversely extending shaft 61 rigidly fixed at its ends to the plates 48. A piston 63 is slidably supported inside of the cylinder 60 and has a downwardly extending piston rod 64 articulately mounted to a rearwardly extending bracket member 65 fastened to the rear side of the plate 45. Thus, as the piston 63 moves upwardly and downwardly, the plate 45 will move upwardly and downwardly with the upper end moving in an arcuate path tangent generally to the vertical plane and the lower end moving in an arcuate path tangent to a plane extending downwardly and rearwardly generally at an angle of approximately 45.

The upper and lower ends of the cylinder 60 are connected through hydraulic conduits 70, 71 respectively through a valve 72 to a hydraulic pump 73. The valve 72 is relatively conventional in construction and has an up, a down and a neutral position. The pump 73 is also connected to an oil reservoir 74.

The valve 72 is preferably arranged so that when in the neutral position, hydraulic fluid can neither flow into nor out of either the upper or the lower end of the cylinder 60. This in effect locks the vertical position of the blade B relative to the vehicle A. To initially place the plow B in operation, it is mounted on the front end of the vehicle A with the hydraulic piston being in such a position that the leading edge of the fingers 25 is either just in engagement with the road surface 15 or has a slight clearance therefrom. In this position, the piston 63 is preferably midway between each end of its stroke. The position of the skids 30 is then so adjusted by rotating the shaft 31 that all of the weight of the plow blade B is carried by the skids 30 so that if the pressure from the lower side of the piston 63 is removed, the leading edge of the fingers 25 will remain with their preadjusted clearance. The nut 33 may then be tightened to maintain this position of the shaft 31. The plow is then ready for normal plowing operation.

Depending upon the clearance established and assuming a perfectly flat road surface 15, all snow down to this clearance will 'be readily and quickly removed. In the event that the snow is hard packed or has turned to ice, however, it has been the experience that the normal plow blade as so operated is unable to remove all of this hard packed snow or ice and this is so even though the entire weight of the blade itself is allowed to press downwardly.

In accordance with the present invention, however, the mechanism above described enables a large part of the unsprung weight of the vehicle A to be transferred to the plow B such that the pressure of the leading edge of the fingers 25 on the road surface 15 can be enormously increased. As this happens, of course, the fingers 25 may retract slightly so that the fingers instead of always being biased to their most forward and downward position, will be in a slightly retracted and upward position. With this arrangement, an extremely large pressure can be obtained between the leading edge of the fingers and the road surface and yet these fingers are resiliently floating on a plane which extends upwardly and rearwardly. The fingers thus have two components of motion, namely, vertically up and down and fore and aft. As the plow B goes forward, these fingers are constantly working in these two directions to compensate for any variations in the road surface 15. Whenever an obstruction such as a manhole cover or a raised runway light in an airport runway is encountered, the fingers which contact the obstruction retract sufficiently that the leading edge is raised enough to clear the obstruction then pass over the obstruction in pressure engagement therewith and as soon as the obstruction is passed, they immediately advance forwardly and downwardly to again contact the road surface 15.

It is to be noted that if the hydraulic mechanism simply moved the plow B in a vertical plane, that it would be necessary when it was desired to transfer the weight of the vehicle A to the fingers 25 and have them pres-s against the road surface with a substantial pressure, to retract the skids 30 so that they do not carry the weight of the vehicle A but rather that the weight is transferred to the fingers 25. This may be accomplished, of course, by making the shaft 31 hydraulically retractable, but in the preferred embodiment of the invention, this is done automatically by the use of the two toggle members 46, 47 of a different length. Thus, when the plow B is moved downwardly relative to the vehicle A, the upper edge of the plow B is tilted forwardly relative to the lower edge and the effect is that the skids 30 are automatically raised at this time as is shown in FIG- URE 2. With this arrangement, all of the weight of the plow B and as much of the weight of the unsprung weight of the vehicle A as is desired may be transferred to the leading edge of the fingers 25. It is, of course, to be appreciated that if the vehicle A is of the fore and aft drive type, some of the drive traction of the forward wheels will be lost, but practice has shown that this is in no ways detrimental, it being noted that almost all vehicles employed for the purpose of driving plows have a relatively large and very heavy motor normally located over the front wheels 10. Thus, there is always ample or even excessive weight to obtain driving traction on these front wheels and a slight transfer of weight to the plow B is not in any way detrimental.

As is shown in FIGURE 2, when the plow B is forcefully moved downwardly by transferring some of the weight of the vehicle A to the plow B, the sprung weight on the wheels 10 is reduced and the springs 13 Hex so that the frame 12 moves slightly upwardly.

The invention has been described with reference to a preferred embodiment. Obviously, modifications and alterations will occur to others upon a reading and understanding of this specification.

Having thus described my invention, I claim:

1. In a vehicle mounted snow plow arrangement comprised of a vehicle having wheels, a frame and spring means mounting the frame relative to the wheels, a snow plow blade having a leading lower edge adapted to engage the surface to be plowed and means mounting said blade in front of said frame, said means including a first member mounted to said frame and a second member mounted to said snow plow blade, upper and lower toggles supporting said members for generally vertical movement relative to each other, the upper toggle member being shorter than the lower toggle member and extending gene ally horizontally, the lower toggle member extending forwardly and downwardly, whereby when the forward member moves downwardly, its upper edge tilts forwardly so that when said blade is moved downwardly relative to the vehicle frame, the blade is tilted forwardly and means for forcefully moving said blade downwardly relative to said vehicle frame and transferring part of the sprung weight of the vehicle to the blade edge.

2. The combination of claim 1 wherein said plow blade includes slide members located behind its cutting edge and normally adjusted to engage the surface to be plowed and provide a clearance for the cutting edge of said blade, the tilting of said blade forwardly by downward movement, raising said skids relative to said cutting edge whereby the cutting edge can engage the surface to be plowed with a high pressure engagement.

3. The combination of claim 1 where the leading edge of said blade is formed by a plurality of fingers in side-byside relationship mounted for movement upwardly and rearwardly relative to said blade and means biasing said fingers forwardly and downwardly.

4. In a motor driven vehicle driven snow plow arrangement including a motor vehicle having wheels, a frame including a front end therefor, spring means movably springing said frame in a vertical direction relative to the wheels and a snow plow means including a snow plow blade mounted on the front end of the frame and having a lower edge adapted to contact a surface for the purpose of removing snow and ice therefrom, the improvement which comprises:

means mounting the blade relative to the frame for transferring at least a portion of the sprung weight of the vehicle from the spring means of the vehicle to the'lower edge of said blade;

said snow plow means further including slide means behind said lower edge of the plow blade; and means for automatically raising the slide means relative to said lower edge when at least some of the weight of the vehicle is transferred to the lower edge.

References Cited Coontz 37144 ABRAHAM G. STONE, Primary Examiner.

A. E. KOPECKI, Assistant Examiner. 

